Clothes drying machines



July 15, 1958 J. D. WARHUS 2,842,854

CLOTHES DRYING MACHINES Filed July 19, 1956 FIG. 1 Q L 3 W/f? 50/50 SOURCE 236M1 40. k w

BUAPEME 11/7' 4 POLE 57497:

imp QMOBMZW nited States 2,342,6 3 Patented July 15, 1958 CLOTHES DRYING MACHENES John ll). Warhus, Lombard, Iil., assignor to General Electric Company, a corporation of New York Application July 19, 1956, Serial No. 598,733

7 Claims. (Cl. 34-45) The present invention relates to clothes drying machanies f the home laundry type, and more particularly to improved control circuits therefor that facilitate selective :presetting of the drying conditions thereof to accommodate the drying of dilterent types of fabrics in a ready and simple manner.

An object of the invention is to provide in a clothes drying machine of the character noted, an improved control circuit incorporating an electric drive motor of the twospeed split-phase induction type, whereby the mere preselection of the operating speed of the drive motor presets the dry-ing conditions of the machine respectively suitably to light fabrics and to heavy fabrics.

Another object of the invention is to provide in a clothes drying machine, an improved control arrangement of the character noted, in which the selection of one of the two drive motor speeds automatically presets one of two corresponding tumbling speeds of the clothes-receiving drum and one of two corresponding rates of circulation of hot air through the drum, whereby this selection automatically presets one of two corresponding temperatures for the hot air current respectively suitably to light fabrics and to heavy fabrics.

A further object of the invention is to provide in a clothes drying machine, a control circuit of improved and simplified connection and arrangement facilitating ready presetting of the machine to the drying of fabrics of widely different character under substantially ideally individual drying conditions.

Further features of the invention pertain to the particular arrangement of the elements of the clothes drying machine and of the control circuit therefor, whereby the above-outlined and additional operating features thereof are attained.

The invention, both as to its organization and method of operatic-11, together with further objects and advantages thereof, will best be understood by reference to the following specification taken in connection with the accompanying drawing, in which:

Figure l is a schematic illustration of a clothes drying machine embodying the present invention, this view comprising, in part, a vertical sectional view taken from the rear of the machine in the direction of the arrows along the line i-l in Fig. 2;

Fig. 2 is a schematic illustration of the clothes drying n chine, this View comprising, in part, a vertical sectional view taken from the side of the machine in the direction of the arrows along the line Z2 in Fig. 1; and

Fig. 3 is a diagrammatic illustration of the control circuit incorporated in the machine of Figs, 1 and 2.

i-ieferring now to Figs. 1 and 2 of the drawing, the clothes drying machine it) there illustrated and embodying the features of the present invention comprises an upstanding substantially box-like housing ll enclosing a substantially tubular casing 12, that, in turn, encloses a substantially cylindrical drum 13 adapted to receive the clothes to be dried and mounted for rotation about a substantially horizontal axis. The front wall of the housing 11, the front wall of the casing 12 and the front wall of the drum 13 have aligned front openings therein that are selectively opened and closed by a cooperating front door 1 carried by the front wall of the housing 11. The drum 13 includes a substantially cylindrical perforated side wall 25 (the perforations being indicated at 16), and the casing 12 includes a substantially scroll-shaped side wall 17, the side walls and 17 being arranged eccentrically with respect to each other so as to define a heating chamber 18 therebetween adjacent to the lefthand side of the machine id, as viewed from the rear. Also the casing 12 is provided with a downwardly directed air inlet conduit 19 communicating with the lower portion of the heating chamber 18 and with an outwardly directed air discharge conduit 20 disposed on the right-hand side of the machine It), as viewed from the rear. Further the extreme outer end of the air discharge conduit 20 communicates with the exterior through a cooperating opening provided in the right-hand side wall of the housing 11, as viewed from the rear; and within the outer end of the air discharge conduit 2%? there is arranged a lint trap 21. Also the side wall 15 of the drum 13 carries a plurality of angularly space-apart and inwardly radially directed clothes tumbling vanes 22, three of the vanes 22 being indicated.

Also the machine It comprises an electric drive motor 23 of the two-speed split-phase induction type including a rotor M (see Fig. 3) provided with an operating shaft 25, as well as a blower or fan 26 including a rotor 27 directly secured to the operating shaft and a casing 28 enclosing the rotor 2'7. The casing 28 is of substantially scroll-shape including an air intake port 29 and an air discharge port 36, the air discharge port 36 being connected to the air inlet conduit 19 by a tube 31. Also the extreme outer end of the operating shaft 25 carries a pulley 32 that is connected by a belt 33 to a pulley 34 carried by an idler shaft 35. Further, the idler shaft 35 carries a pulley 36 that is connected by a belt 37 to a pulley 32 carried by a stub shaft 39; which stub shaft 39 is suitably secured to the rear wall of the drum 13.

In view of the foregoing, it will be understood that when the drive motor 23 is operated the drive shaft 25 is rotated effecting operation of the blower 26 and rotation of the drum 13, in the counterclockwise direction as viewed from the rear of the machine 10. More particularly, the rotating operating shaft 25 rotates the rotor in the casing 28, so that air in the housing 11 is drawn into the intake port 29 and discharged via the discharge port 30, the tube 31 and the air inlet conduit 19 into the heating chamber 18. Also the rotating operating shaft 25 rotates the idler shaft 35 and the rotating idler shaft 35 rotates the stub shaft 39, whereby the drum 13 is rotated as previously noted, so that the clothes tumbling vanes 22 effect tumbling of the clothes in the rotating drum 1?.

Arranged within the heating chamber 13 is an electric heating element all of substantially sinuous form, and a series of louvers 41; whereby the air introduced into the heating chamber 18 is directed by the louvers 41 over the heating unit 40 and thence through the perforations 16 formed in the side wall 15 of the rotating drum 13; whereby the current of air is heated and passes into the drum 13 into contact with the clothes tumbling therein. The current of air leaves the drum 13 through the perforations 16 formed in the side wall 15 adjacent to the air discharge conduit 20; which current of air passes through the lint trap 21 and thence to the exterior. Accordingly, it will be understood that the air taken into the blower 26 is circulated across the electric heating unit 40; whereby it is heated and dried incident to energization of the electric heating unit 49. The hot current of air then passes through the drum 13 into contact with the clothes aesasee J tumbling therein so as to effect evaporation of the moisture carried thereby; and ultimately the air is discharged from the drum 13 via the air discharge conduit 2% and the lint trap 21 to the exterior of the housing 11.

The machine it? further comprises a control circuit, as illustrated in Fig. 3, that includes the drive motor 23 of the two-speed split-phase type previously mentioned, and specifically of the 4-pole-6-pole type. More particularly, the motor 23 also comprises a stator, not shown, that carries a l-pole start winding 42, a 4-pole run winding 43, and a 6-pole run winding 44; the rotor 24 is provided with a squirrel-cage winding 45; and the operating shaft 25 carries a speed-responsive device 46 that governs an operating element 47 carrying three contact bridging members .48, 49 and 5th. The contact bridging member 48 governs an associated pair of front contacts; the tact bridging member 49 also governs an associated pair of front contacts; and the contact bridging member governs a set of three backcontacts and a pair of front contacts, all for a purpose more fully explained herein-- after. More particularly, when the rotor 24 is at rest and also at a speed below a critical speed, the contact bridging members 43 and 49 occupy their open positions, and the contact bridging member 59 closes the set of three back contacts and opens the pair of front contacts. On the other hand, when the rotor 24 is rotated at a speed above the critical speed, the speed-responsive device d5 governs the operating element 47 to close the contact bridging members 48 and 49 and to operate the contact bridging member 50 so as to open the set of three back contacts and to close the pair of front contacts.

In the arrangement: when the motor 23 is operated as a 4-pole motor, the normal full load operating speed thereof is approximately 1725 R. P. M.; and when the motor 23 is operated as a 6-pole motor, the normal full load operating speed thereof is approximately 1140 R. P. M. Accordingly, when the motor 23 is operated as a 4-pole motor, the drum 13 is rotated at a speed of about 56 R. P. M., and when the motor 23 is operated as a 6-pole motor, the drum 13 is rotated at a speed of about 37 R. P. M., by virtue of the speed-reduction achieved by the arrangement including the idler shaft 35. Preferably the drum 13 has a diameter of about 26"; whereby it is rotated at a peripheral speed in the general range 350 to 410 feet per minute, when the motor 23 is operated as a 4-pole motor; and whereby it is rotated at a peripheral speed in the general range 230 to 270 feet per minute when the motor 23 is operated as a 6-pole motor.

Continuing the reference to Fig. 3, the control circuit further comprises a three-wire Edison source of current supply of 236-volts, single-phase, A. 0, including two outside ungrounded conductors 51 and 52 and a neutral grounded conductor 53. Also the front wall of the housing 11 carries a control plate 54, that, in turn, carries a first manually operable control knob or dial 55 forming a part of a timer 56, and a second manually operable control knob or dial 57 forming a part of a switch 53. The dial 55 carries time indicia that cooperates with a time index marker 59 carried by the plate 54; while the dial 57 carries an index pointer 60 that cooperates with indicia heavy fabrics and light fabrics carried by the plate 54-. More particularly, the timer 56 is provided with a rotatably mounted operating shaft 61 carrying two insulating control cams C1 and C2 respectively cooperating with two sets of switch springs S1 and S2, the outer end of' the operating shaft 61 carryin the manual dial 55, as previously noted. Also the timer 56 comprises a timer motor 62 of the synchronous type provided with an operating shaft 63 that is connected to escapement mechanism 64 provided with an operating shaft 65. The inner end of the operating shaft 63. is connected to the operating shaft 65 by a friction clutch 66 that accommo dates rotation of the operating shaft 61 by the manual dial 55 independently of the escapement mechanism 64.

In the arrangement, when the manual dial 55 is rotated out of its off position into its variable on or time position, operation of the timer motor 62 is initiated; whereby the escapement mechanism 64 drives the operating shaft 61 through the friction clutch 66 step by step back into its off position, so that operation of the timer motor 62 is arrested while the manual dial 55 occupies its off position.

The switch 53 comprises a rotatably mounted operating shaft 67, the outer end of which carries the manual dial 57 and the inner end of which carries a contact wiper 68 that cooperates with a contact ring 69 and selectively with two angularly spaced-apart contact segments 70 and 71. More particularly, when the manual dial 57 occupies its heavy fabrics position, the operating shaft 67 is rotated to cause the contact wiper 68 to engage the contact segment 7%, thereby to connect together the contact ring 69 and the contact segment 70. On the other hand, when the manual dial 57 occupies its light fabrics position, the operating shaft 67 is rotated to cause the contact wiper 68 to engage the contact segment 71, thereby to connect together the contact ring 69 and the contact segment 71.

in the circuit arrangement: the outside conductor 51. is connected to one switch spring of the set S1 and the other switch spring of the set S1 is connected to a conductor 72; the outside conductor 52 is connected to one switch spring of the set S2 and the other switch spring of the set S2 is connected to a conductor 73, and the neutral conductor 53 is commonly connected to one terminal of the timer motor 62, and to one terminal of each of the windings 42, 43 and 44 of the drive motor 23. The other terminal of the timer motor 62 is connected to the conductor '73; the other terminal of the winding 42 is connected to a conductor 74, the other terminal of the winding 43 is connected to a conductor 75; and the other terminal of the winding 44 is connected to a conductor 76. The conductor 73 is further connected to the contact ring 69 and to the left contact of the pair associated with the contact bridging member 48; the conductor 72 is further connected to the left contact of the pair associated with the contact bridging member 49; the right contact associated with the contact bridging member 48 terminates a conductor 77 that is connected to one terminal of the heating unit 40; and the right contact of the pair associated with the contact bridging member 49 terminates a conductor 78 that is connected to the other terminal of the heating unit 40. The conductor 74 is connected to the right-hand back contact of the set associated with the contact bridging member 50; the middle back contact of this set is connected to a conductor 79; and the left-hand back contact of this set is connected to the conductor 75. The right-hand front contact associated with the contact bridging member 50 is also connected to the conductor 79; and the left-hand front contact of this set is connected to the conductor 76. Further, the conductor 79 is connected to the contact segment 76; and the conductor 75 is further connected to the contact segment 71.

In the circuit arrangement, when the timer switch 56 occupies its off position, the sets of switch springs S1 and S2 occupy their open positions, thereby to interrupt the circuits for operating the timer motor 62 and the drive motor 23 and for energizing the electric heater 40.

In operating the machine 10, the housewife places the wet clothes to be dried into the drum 13 when the front door 14 occupies its open position, and then cioscs the front door 14 with respect to the housing 11. Next, the housewife determines whether the clothes that have been placed in the drum 13 comprise heavy fabrics or light fabrics; and for the purpose of the present description, it is assumed that the clothes mentioned comprise heavy fabrics so that the manual dial 51 is rotated into its heavy fabrics position illustrated. Finally, the housewife determines the appropriate drying time and correspondingly rotates the manual dial 55 out of its off position into itsvariable or time position. In the ar- U rangement, the skirt of the manual dial 55 has been illustrated as being calibrated in minutes on a scale from 10 to 70; however, this: scheme is entirely illustrative and is in no way critical.

When the manual dial 55 is rotated out of its ofi position into its variable on or time position, the operating shaft 6?. is rotated with respect to the operating shaft 65 by virtue of the provision of the friction clutch 66, and the control cams C1 and C2 operate the sets of switch springs S1 and S2 into their closed positions; whereby the outside conductors 51 and 52 are respectively connected to the conductors 72 and 73. The connection of potential to the conductor 73 completes a circuit for operating the timer motor 62; whereby the escapement mechanism 64 is operated step by step as time proceeds to effect step-by-step rotation of the operating shaft 61 back into its 01f position. More particularly, the manual dial 55 is initially rotated from its off position in the clockwise direction into its variable or time position; and the operating shaft 61 is rotated further in the clockwise direction by the timer motor 62 through the escapement mechanism as and friction clutch 66 and ultimately back into its off position at the conclusion of the set time interval.

Also the application of potential to the conductor 73 completes parallel circuits for energizing the 4-pole start winding 42 and the 4-poie run winding 43 of the drive motor 23. Specifically, the conductor 73 is connected via the contact ring 65' and the contact wiper 68 to the contact segment 79 and thence to the conductor 79; the conductor 79 is connected to the middle back con tact of the set associated with the contact bridging memher Sti and consequently to the right-hand back contact and to the left-hand back contact of this set and thus to the conductors 7 i and 75. Accordingly of the winding 41 is energized between the conductor 74 and the neutral conductor 53; while the winding s3 is energized between the conductor 75 and the neutral conductor 53; whereby operation of the drive motor 23 is initiated. Specifically, rotation of the rotor 24 is initiated, and when the same is accelerated to a speed somewhat in excess of one-half of its normal 4-pole operating speed, the speed-responsive device 46 is operated to move the contact bridging member t) from its normal position into its operated position. Movement of the contact bridging member 50 out of its normal position interrupts the previously traced circuits for energizing the windings 4,2 and 43; while movement of the contact bridging member 56 into its operated position completes a circuit for energizing the 6-pole run winding cludes the conductors 79 and 76 and the front contacts of the set now closed by the contact bridging member 56). Hence at this time, the windings 42 and 43 are deenergized and the winding 44 is energized; whereby the rotor is accelerated on into its normal 6-pole running speed of about 1140 R. P. M.

Also when the speed-responsive device 46 is operated in the manner described above, the contact bridging members 48 and 4-9 are operated into their closed positions connecting the conductors 77 and 78 to the conductors 73 and 72; whereby a circuit is completed, also including the closed sets of switch springs S2 and S1, for energizing the heating unit 4i? across the outside conductors 51 and 52 of the three-wire Edison source.

The operating drive motor 23 operates the blower 26 and rotates the drum 13, while the energized heating unit 40 produces heat, all in the manner previously explained. At this time, the drum i3 is rotated at a relatively low tumbling speed of about 37 R. P. M. by virtue of the operation of the drive motor 23 as a 6-pole motor. Similarly, the blower 26 is operated at a relatively low'speed in order to deliver a relatively low volume of air to the heating chamber 18 by virtue of the operation of the drive motor 23 as a -pole motor. Since the heating unit 40 develops a predetermined wattage when connected The last-mentioned circuit ind across the outside conductors 51 and 52 it is apparent that the temperature thereof, and consequently the ultimate temperature of the air stream passing through the rotating drum 30, is inverseiy proportional to the rate of flow of the current of air blown thereover. Accordingly, in the present instance, since a relatively low rate of flow of air is circulated over the heating unit 40, the temperature thereof is relatively high; whereby the current of air is heated to a relatively high temperature with the result that the tumbling clothes in the rotating drum 31 are heated to a relatively high temperature that is suitable to the drying of heavy fabrics.

At the conclusion of the time interval preset upon the manual dial 55, the timer 56 is rotated back into its oif position, as previously explained, whereby the control cams C1 and C2 operate the sets of switch springs S1 and S2 back into their open positions to interrupt the circuits for operating the timer motor 62 and for operating the drive motor 23 and for energizing the heating unit 40. Specifically, operation of the timer motor 62 is arrested when the manual dial 55 occupies its off position; and when operation of the drive motor 23 is arrested, the speed-responsive device 46 restores the contact bridging member back into its back position repreparing the circuits for energizing the 4-pole start winding 42 and the 4-pole run winding 43 of the drive motor 23. Also the contact bridging members 48 and 49 are returned into their open position interrupting further points in the circuit for energizing the heating unit 4%. At this time, the drying cycle has been completed and the clothes may be removed from the drum 13 after the front door 14 is moved into its open position.

Considering now the operation of the machine 10 to efiect a drying cycle involving light fabrics, the housewife rotates the manual dial 57 into its light fabrics position and rotates the manual dial into the desired time position, after placing the fabrics in the drum l3 and closing the front door 1.4. Rotation of the manual dial 57 into its light fabrics position operates the switch 58 into its corresponding position; whereby the contact wiper disengages the contact'segment and engages the contact segment 71, for a purpose more fully explained below. When the manual dial 55 is rotated out of its oif position into its variable on or time position, the control cams C1 and C2 close the sets of switch springs S1 and S2, completing the circuit for operating the timer motor 62 and for energizing the windings 42 and 43 of the drive motor 23 in the manner previously explained. In this case, the circuit for energizing the 4-pole start winding 42 includes the conductors 73, the contact ring 69, the contact wiper 68, the engaged contact segment 71, the conductor 75, the left-hand back contact engaged by the bridging member 50, the bridging member 50, the right-hand back contact engaged by the bridging member 50 and the conductor 74; while the circuit for energizing the 4-po1e run winding 43 includes the conductor 73, the contact ring 69, the contact wiper 68, the engaged contact segment 71 and the conductor 75. Accordingly, rotation of the rotor 24 is initiated in the manner previously explained; and when the critical speed thereof is reached, the speed-responsive device 46 is operated to move the contact bridging memher 50 from its normal restored position into its operated position. When the contact bridging member 5") disengages the three back contacts of the associated set, it interrupts the above-traced circuit for energizing the 4-pole start winding 42, but it does not interrupt the previously traced circuit for energizing the 4-pole run winding 43. When the contact bridging member 56 engages the pair of front contacts, it prepares the circuit for energizing the 6-pole run winding 44; which circuit is not completed in the present instance since the contact wiper 65 disengages the contact segments 70 and engages the contact segment 71 in the light fabrics position of the manual dial 57. Accordingly, in the present example, the energization of the 4-pole run winding 43 is continuous so that h t a rel igh rate of air circulation over the heatin L lace with the result that the current of air a relatively low temperature bring'nr;

about "ending heating of the tumbling clothes in the rotating drum 1?; to a relatively low temperature; which ts rotor: is suitable to the drying of light fabrics. n passing, it is mentioned that the operation of the speedsivc device no in this case also operates the contact s and into their closed position to t energization of the heating unit it), in the manner of the ime interval set upon the manmotor 62 returns the timer 56 bacl: whereby the control cams Cl and C2 return the our.) L switch springs S1 and S2 back into their open positions so to interrupt the circuits for operating the timer motor 62 and the drive motor 23 and for energizi the heating unit so; whereby the operation of the machine 1% is terminated in the manner previously eX- ;slaincd, so rat the clothes may be removed from the drum 23 mm opening of the front door 14 with respect to the housing ll.

By way of recapitulation, it is pointed out that when the machine is operated in either its heavy fabrics cycle or in its light fabrics cycle, the time interval of operation is selectively set by the manual dial 55 and the rate of heat production by the heating unit 40 is constant, as tie heating unit has a predetermined and fixed wattage rating. The cycle or drying condition of the machine it is preset by the position of the selector switch 53; whereby in the heavy fabrics position of the selector switch 58, the drive motor 23 is operated as a 6-pole motor at a full load running speed of about 1140 R. P. M.; and whereby in the light fabrics position of the selector switch 53, the drive motor 23 is operated as a 4-pole motor at a full load running speed of about i725 R. P. M. When the drive motor 23 is operated a 6- pole motor, the drum 13 is rotated at a relatively low tumbling speed of about 37 R. P. M.; and when the drive motor 23 is operated as a 4-pole motor, the drum 13 is rotated at a relatively high tumbling speed of about 56 R. P. M. Similarly, when the drive motor 23 is operated a 6-pole motor, the blower is operated at a relainto its on Add tively low volume of air movement; and when the drive motor 23 is operated as a l-pole motor, the blower 26 is operated at a relatively high volume of air movement. Since the heating rate of the heating unit 4b is constant, the temperature to which the current of air is heated is substantially inversely proportional to the rate of movement thereacross; whereby the temperature of the air current is respectively relatively high and relatively low when the air movement is respectively relatively low and relatively high. Accordingly, the tumbling clothes in the drum 1?: are heated to a relatively high temperature when the selector switch 58 occupies its heavy fabrics position, which temperature is suitable to the drying of heavy rics; on the other hand, the tumblin clothes in the drum 13 are heated to a relatively low tem erature when the selector switch 58 occupies its light fabrics posi tion, which temperature is suitable to the drying of light fabrics.

in the foregoing explanation of the mode of opera of the machine i lgit is intended that the expre. heavy fabrics should embrace not only fabrics that are in fact heavy in weight, but also those fabrics which carry a great weight of moisture to be dried therefrom; and that the expression light fabrics should embrace not only fabrics that are in fact light in weight, but also C ll those fabrics which carry a small weight of moisture to be dried therefrom. Thus ordinary cotton and linen fabrics comprise heavy fabrics; whereas silk, rayon, nylon, Orion, etc., fabrics comprise light fabrics. Moreover heavy cotton turkish towels would comprise heavy fabrics; whereas light cotton tea towels would comprise light fabrics.

This classification of fabrics is not intended to be a rigorous one, but rather an indication of the character 1 crcof with respect to the temperature at which these fabrics are ordinarily dried in clothes drying machines of the home laundry type.

In view of the foregoing, it is apparent that there has been provided in a clothes drying machine of the home laundry type an improved and simplified control circuit therefor, whereby the drying cycle of operation of the machine may be selectively and readily set by selectively setting the speed of operation of the two-speed splitphase drive motor for the machine.

While there has been described what is at present considered to be the preferred embodiment of the invention, it will be understood that various modifications may be made therein, and it is intended to cover in the appended claims all such modifications as fall within the true spirit and scope of the invention.

What is claimed is:

l. in a clothes drying machine including a drum mounted for rotation about a substantially horizontal L. .is and adapted to receive and to tumble the clothes to be dried, a casing enclosing said drum, a blower operative to translate a current of air in said casing and through said drum and into contact with the clothes tumbling therein, and a heater operative to heat said current of air so as to effect evaporation of the moisture carried by the clothes tumbling in said drum; the combination comprising an electric drive motor operative to rotate said drum and to operate said blower, said motor being of the two-speed split-phase induction type including a start winding and two corresponding run windings, said motor being operated at its relatively high speed when a first of its run windings is energized to effect a relatively high tumbling speed of rotation of said drum and a relatively high air volume operation of said blower, said motor being operated at its relatively low speed when a second of its run windings is energized to effect a relatively low tumbling speed of rotation of said drum and a relatively low air volume operation of said blower, operation of said heater in conjunction with said high tumbling speed of rotation of said drum and said high air volume operation of said blower effecting a relatively low temperature in said drum suitable to the drying of light fabrics, operation of said heater in conjunction with said low tumbling speed of rotation of said drum and said low air volume operation of said blower effecting a relatively high temperature in said drum suitable to the drying of heavy fabrics, switching apparatus having first and second positions respectively selecting said first run winding and said second run winding to be energized, means for selectively operating said switching apparatus into its first and second positions, a device responsive to the speed of said motor and having corresp n 'ig start and run positions, means governed by device for energizing both said start winding and a predetermined one of said run windings in the start position there of and for energizing only the selected one of said run windings in the run position thereof, and a master switch for controlling both the energization of said motor and the operation of said heater.

2. The clothes drying machine combination set forth in claim 1, wherein said first run winding has N poles and said second run winding has M poles, where N and M are even numbers and M N.

3. The clothes drying machine combination set forth in claim 2, where N=4 and M :6;

4. The clothes drying machine combination set forth asaasea t. i: r

dried, a casing enclosing said drum, a blower operative 71 to translate a current of air in said casing and through said drum and into contact with the clothes tumbling therein, and a heater operative to heat said current of air so as to effect evaporation of the moisture carried by the clothes tumbling in said drum; the combination comprising an electric drive motor operative to rotate said drum and to operate said blower, said motor being of the two-speed split-phase induction type including a start winding and two corresponding run windings, said motor being operated at its relatively high speed when a first of its run windings is energized to efiect a relatively high tumbling speed of rotation of said drum and a relatively high air volume operation of said blower, said motor being operated at its relatively low speed when a second of its run windings is energized to efiect a relatively low tumbling speed of rotation of said drum and a relatively low air volume operation of said blower, operation of said heater in conjunction with said high tumbling speed of rotation of said drum and said high air volume operation of said blower effecting a relatively low temperature in said drum suitable to the drying of light fabrics, operation of said heater in conjunction with said low tumbling speed of rotation of said drum and said low air volume operation of said blower effecting a relatively high temperature in said drum suitable to the drying of heavy fabrics, switching apparatus having first and second positions respectively selecting said first run winding and said second run winding to be energized, means for selectively operating said switching apparatus into its first and second positions, a device responsive to the speed of said motor and having corresponding start and run positions, means governed by said device for energizing both said start winding and a predetermined one of said run windings in the start position thereof and for energizing only the selected one of said run windings, in the run position thereof, and a manually settable timer for controlling both the energization of said motor and the operation of said heater.

6. In a clothes drying machine including a drum mounted for rotation about a substantially horizontal axis and adapted to receive and to tumble the clothes to be dried, a casing enclosing said drum, a blower operative to translate a current of air in said casing and through said drum and into contact with the clothes tumbling therein, and a heater operative to heat said current of air so as to effect evaporation of the moisture carried by the clothes tumbling in said drum; the combination comprising an electric drive motor of the twospeed split-phase induction type inciuding a start winding and two corresponding run windings, a first drive connection between said motor and said drum, whereby said drum is rotated at a relatively high tumbling speed and at a relatively low tumbling speed is responsive to operation of said motor respectively at its relatively high speed and at its relatively low speed, a second drive connection between said motor and said blower, whereby said blower is operated at a relatively high volume of air movement and at a relatively low volume of air movement in response to operation of said motor respectively at its relatively high speed and at its relatively low speed, operation of said heater in conjunction with said high tumbling speed of rotation of said drum and said high volume of air movement operation of said blower effecting a relatively low temperature in said drum suitable to the drying of light fabrics, operation of said heater in conjunction with said low tumbling speed of rotation of said drum and said low volume of air movement operation of said blower eflecting a relatively high temperature in said drum suitable to the drying of heavy fabrics, switching apparatus having first and second positions respectively selecting said first run winding and said second run winding to be energized, means for selectively operating said switching apparatus into its first and second positions, a device responsive to the speed of said motor and having corresponding start and run positions, means governed by said device for energizing both said start winding and a predetermined one of said run windings in the start position thereof and for energizing only the selected one of said run windings in the run position thereof, and a master switch for controlling both the energizing of said motor and the operation of said heater.

7. The clothes drying machine combination set forth in claim 6, wherein said first drive connection comprises a direct connection between an operating shaft of said motor and a rotor of said blower, and said second drive connection comprises speed-reduction mechanism arranged between the operating shaft of said motor and said drum.

References Cited in the file of this patent UNITED STATES PATENTS 750,535 Goings Jan. 26, 1904 2,048,743 Huebsch et al. July 28, 1936 2,328,256 Breckenbridge Aug. 31, 1943 2,550,118 Kaufiman Apr. 24, 1951 2,789,367 Mayhan Apr. 23, 1957 

